Fig. 5. Bves localization during epithelium formation. (A) REC culture during epithelial formation (A) and at confluence (B). Prominent staining at the periphery of single cells and at the free surfaces of cells is absent (A,C, arrowhead). As the cells become confluent and form the epithelial sheet, uniform cell membrane localization is observed (B). Higher power images (C-F) show the deposition of Bves during sheet formation. Note that Bves localization is detected at the point of cell contact or newly made cell-cell boundaries (D,E, arrows). As the epithelial sheet forms, Bves accumulates around the entire cell surface. In mature epithelial sheets, cytoplasmic staining is greatly diminished (B,F). (G-I) Blocking antibody alters the generation of epithelium in REC. REC form epithelial sheets in Ca2+-free conditions (G). When Bves blocking antibody was added at 1:100 dilution in the medium, semi-confluent REC cells were unable to form the epithelial sheet (H). Higher magnification of treated culture is given in I. (J-K) Bves accumulates at points of cell contact and cell borders prior to E-cadherin. The leading edges of REC epithelial sheets during wound healing in vitro are shown 8 hours after injury. (J) Anti-Bves (B846) is detected in cell processes, punctuate structures along the cell/cell boundaries and as continuous borders between cells (arrows, J,L). (K) E-cadherin in the same cells is broadly distributed in the cytoplasm and at low levels in processes and at cell edges. (L) Merged image of J and K.
